On Tue, Sep 12, 2023 at 10:11 AM, Stephan Ahonen KE0WVA wrote:
I have one of sitting in front of me right now. Very unsophisticated construction, regular old off the shelf 1-watt resistors, the nanoVNA tells me it's within 1 ohm of the bullseye on the smith chart all the way up to 20 MHz. Seems to me that HF and below is pretty forgiving
Absolutely so.
As a further aside, the interesting if slighly simmering discussion around performance of typical amateur homebrew "bog standard" attenuators and dummy loads does leave me pondering quietly quite how much an error of, say, 1dB ever really matters.? They all "add up" of course and so we want to get the best we can out of every stage of a radio contact, but in absolute terms we're for the most part exploiting (battling?) an ionosphere that varies constantly in wonderful ways.? Signal to noise ratios, it seems to me, are the thing - and what's between our ears makes an ultimate measurement there, of intelligibility.
The numbers in power measurements feel worrying perhaps, 7dBW plus or minus or dB is one thing, where the range from 4W through 5W and up to 6.3W may to some seem a huge uncertainty.? But it's just one dB.? The losses through the "aether" from one's QTH to our contact at the other end are likely to be much more uncertain (at HF at least) and we can work to do the best we can without knowing the absolute figures.
Hans provides us with built in test equipment to get best performance out of our builds - it would be a great shame if beginners felt that they needed to invest a lot more to enjoy this wonderful hobby.? Just my two pennyworth.
73
Rod
G0VKX
one-time G8FJN
